Method of and apparatus for evaporating liquid substances



April 22, 1924. 1,491,026

R. G. BRINDLE METHOD OF AND APPARATUS FOR EVAPORATING LIQUID SUBSTANCES Filed Odt. 11. 1918 (aim (ass s: v A

Patented Apr. 22, 1924.

UNITED STATES 1,491,026 PATENT OFFICE.

RICHARD GUY .BBINDLE, OF CHICAGO, ILLINOIS, -ASSIGNOR '10 CORN PBbDUCTS BEFINING COMPANY, ACOBPOBA'IION OF NEW JERSEY.

union or am) mana'rus son. nvarona'rme mqnmsunsrmcns.

Application fled October ll, 19 18. Serial Io. 257,770.,

To all whom it may concern Be it known that. I, Rrcmim G. Bnmnna, a citizen of the United States, residing at Chicago,.in the county of Cook and- State of. Illinois, have invented certain new and useful Improvements in Methods of and Apparatus for Eva crating Liquid Substances, of which the fo owin 1s 'a specification.

My invention re ates to the evaporation of liquids, for exam le,'solutions or liquids containing. solid su tances in suspension, and the object of the invention, generally speaking, is to provide certain improvements in this art whereby the o rations of evaporating the liquid and co 'lecting the resu ting dig substances may beaccomplished more e ectively and economically and with a smaller outlayfor apparatus than is possible with the methods now employed.

The invention has in view particularly the economizing of fuel by the employment of arrangements for re-usin contmuously, a considerable portion of the eated air outflowing from the evaporation chamber. The invention also provides a novel system of collecting the dried material which rmits I the use of small, simple, and re atively nectedbya cheaply constructed dust collectors'without loss of any appreciable part of the output. Other incidental objects will appear from the following description of the invention.

A suitable apparatus embodying the improvements constituting the invention is shown in the accompanying drawin which illustrates the apparatus 1n side e evation.

with parts in section, the drawing being diagrammatic in some respects: f

Referring to the drawing, A represents an evaporating chamber within which is arra an atomizing spraynozzle B, of any esired type, which is supplied with 1 liquid through pipe C in which is arranged a pump D, the liquid being drawn from a supply vessel E. his a pipe for supplying 8.11 under presureto nozzle B. G is an air heating device, referably a furnace conflue with a circumferential duet-I surrounding the evaporatig chambar. The airheated in 'furnace passes through flue H and duct I and into the evaporation chamber through tuyenes J. The air comes in contact with the spray from nozzle B at some distance above the point at which the liquid issues from the nozzle.

lcctor The air, vapor and dry particles are'withdrawn from the top of chamber A. by' a fan K through a duct L into a dust collector M, preferably of the cyclone type. The bulk of .the dry material from the evaporating operation'is discharged. from the a paratus at this oint. The air from the 4 passes into a pi N which has two branches,'branch '0 leading back to the bottom of the evaporati spray nozzle B, and ranch P to a heat transfer device Q throu h which is circulated fresh air taken in throughan opening R. The air and suspended particles from pipe P pass into a' header S through pipes T and into a header U, all forming part of the heat transferring device, and thenceinto a dust collectoriV which may be a bag' collector ofany desired construction. The air is drawn from dust collector V by a' fan W in the outlet ipeX. The fresh'airpassing throu 11 the cat transferring device Q is hea to a certain extent and passes through a .pipe Y to the flue H between-furnace G and the evaporat' chamber.

, The velocity of t e air and gases passing net 001- chamber under the...

through the desiccatin chamber is sufiicient to carry over all the so 'd particles.

With the a paratus constructed as shown and descri it is possible to evaporate liquids in a very economical manner. The

= 'be considerably reduced by the introduction of the air which is taken'from the atmosphere and only moderatcly heated in the cat transferring device Q. The bulk of the dry material is separated out by the cyclone dust collector M. The portion of the air from the dust collector which is returned immediately to the evaporation chamber throughpipe 0 serves to produce an'initial drying or eva ration of the liquid treated.

.The heated alr introduced through the tuyercs J, which will be at a higher temperature than the air introduced into the evaporation chamber through pipeO, completes the dryin operation and gives the material the relatively hi h temperature necessary for producing c iemical changes therein when the intended treatment involves such chemical chan s. If the air passing through pipe pension, as will be the case to some extent, such particles are mixed with the spray and consequently are not lost.

- It is not possible to return all of the air from the evaporation chamber back to said chamber as the air in the apparatus would, in such case, eventuall become saturated and the evaporation of iquid cease. A certain portion of the air pasing through duct N is, therefore, discharged into the atmoshere. It first passes, however, through the eat transferring device Q where most .of its heat is given up to the fresh and relatively dry air drawn in through opening R.

It is then passed through the bag dust colleetor V in which a separation is made between air and substantially all of the dry particles suspended therein. The bag dust collectors are effective and can be counted 3 upon to make a very complete separation, but they are somewhat expensive to install issuing from this dust collector a the heater Q is lowered in temperature. it is not sufficiently lowered to bring it to a point of saturation so that moisture would be consjdered within the heater. At the temperature to which the air and gases are originally heated, the gases are capable of absorbing considerably more moisture than they carry out of the evaporating or desiccatmg chamber. In other words, the gases are by no means saturated.

The fresh air drawn through the heat transferring device Q'serves tau-substantially reduce the temperatureof the air entering the tuyer'es J. It will be foundeconemical to maintain a hot fireinthefurnace G and to then reduce the tem ratnre of the air and productsof combustion issuing from the furnace before they go to the evaporation chamber. The temperature maintainedlin the evaporation chamber will, of course, depend upon the character of the material treated and the nature of the changes to be produced therein.

While I have referred to the drying mecontains particles m sus-' dium as air, and for the sake of economy I I prefer to employ air as the drying agent, it will involve no de arture frommy invention to employ anot er gas in place of air.

I claim:

1. In apparatus of the character described, the eombmationof an evaporation chamber, means for spraying liquid therein, an air heater, means for introducing: air into the evaporation. chamber through said air heater, a heat transferring device separate from said air heater, means for causing a draft of fresh air other than-the air heated in said air heater to pass throu h said heat transferring device and into t e evaporationchamber, and means for causing heated air from ,the evaporation chamber to pass through the heat transferring device; said heat transferring device having separate ducts for said fresh air and air taken from the'evaporation chamber. U

2. In apparatus of the character described, the combination .of an evaporation chamber, means for spraying liquid therein, an air heater, means for introducing air into the evaporation chamber through said air heater, :1 heat transferring device separate from said air heater, means for causing-a draft of fresh air other than the air heated in said air heater to pass through said heat transferringdeviceand into the evaporation chamber,,means for causing heated air from the evaporation chamberto pass through the heat transferring device; said heat transferring device having'separate ducts for said fresh air and air taken from the evaporation chamber, and a dust collector-through which .the air from the evaporation chamber is passed after it leaves the heat transferring device.

3. In apparatus of the character described, the combination of an evaporation chamber, means for spraying liquid therein, means for introducing heated air into the ehamber, means for returning part of the air drawn from the evaporation chamber hack to the chamber, a heat transferrin device. means for causing another part 0 the air from the chamberto pass through the heat transferring device, and means for causin fresh air to be 'intrmluced into and ion pass t rough the heat itransferring device,

heated air into the" device through which freshair and the other of the air from the eve ration chamr is circulated, and means or introducing the fresh air when heated in 'said device into the chamber with the air first mentioned so as to reduce the temperature thereof.

5. In apparatus of the character described, the combination of an evaporation chamber, a spraying device therein, an air V 6. In apparatus of the character dek scribed, the combination of an evaporation chamber, a spraying device therein, an air heating device having a duct leading to the evaporation chamber, a heat transfer-rigs device through which fresh air is adapt to. be circulated, a duct leading from the evaporation chamber to said heat transfer ring device, a dust collector through whichthe air from the eva ration chamber is sand after leaving a heat transferring evice, a duct through which fresh air from theheat transferrin device is ssed to said first mention duct, an a duct through which a part of the air from the evaporation chamber. is returned to the evaporation chamber without passing the heat transferring device 7. apparatus of the character described, the combination of an evaporation chamber, a

spray nozzle 'in the bottom of the the evaporation chamber for sprayin h liquid to be treated upwardly throu chamber, a duct surrounding the evapora' tion chamber above the spray nozzle adapted to receive air from sai and ports to deliver said air into .culating through the heat holes from said -the rest of to the said enclosed space spraying air heating device the chamber, a dust collector, and means for withdrawing air from the top of the 60 chamber into said dust collector, a heat. transferring device having a p w: for the circulation therethrough o air, and a passage for air drawn from the evalpm ration chamber, a duct connecting said ust' collector with said lastmamed passage, a branch duct leading from said last named duct to the bottom of the evaporation chamber, a dust collector through which air from the evaporation chamber is after vice, and a duct for introducing the air circulated through the heat device into the duct surrounding the evaporation chamber. I which comclosed 8. Method of treating liquids prises spraying'the liquid into an en space, introducing heated air into said space withdrawing he mand a st eet,

artofsaidairandreturnmgfl material from the charging a contact with the material as thesprayin means.

9. Meth of treating 'ds which comprise spraying the liquid mto an enclosed space, int so that itwill come-into contact with the material at a place beyond the place where the material issues from the spra, means, withdrawing the air and particles from sa d ace, making a eepa-' ration of the so d an a .air, subjecting a part of said air to a further separating operation, the same to the atmosphere, and returning the rest of the air without further separation of solids to the saidenclosed space in contact with the material .'as it issues from the 310mm) our sa p e. I

so that it will come into contact with the i 1e roducmgheatedairintosaidspaee 

